If other exception was raised during exiting an expired
asyncio.timeout() block, insert TimeoutError in the exception context
just above the CancelledError.
asyncio.TaskGroup and asyncio.Timeout classes now raise proper RuntimeError
if they are improperly used.
* When they are used without entering the context manager.
* When they are used after finishing.
* When the context manager is entered more than once (simultaneously or
sequentially).
* If there is no current task when entering the context manager.
They now remain in a consistent state after an exception is thrown,
so subsequent operations can be performed correctly (if they are allowed).
Co-authored-by: James Hilton-Balfe <gobot1234yt@gmail.com>
Also use `raise TimeOut from <CancelledError instance>` so that the CancelledError is set
in the `__cause__` field rather than in the `__context__` field.
Co-authored-by: Guido van Rossum <gvanrossum@gmail.com>
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Example:
async with asyncio.timeout(5):
await some_task()
Will interrupt the await and raise TimeoutError if some_task() takes longer than 5 seconds.
Co-authored-by: Guido van Rossum <guido@python.org>
Serhiy Storchaka
Kristján Valur Jónsson
JosephSBoyle
Thomas Grainger
Andrew Svetlov